/Engine/Plugins/Animation/RigLogic/Source/RigLogicLib/Public/pma/resources/ArenaMemoryResource.h
The growth factor in this case will be 1.0, i.e. no growth.
ArenaMemoryResource ( std::size_t regionSize, [MemoryResource](API\Plugins\RigLogicLib\pma\MemoryResource) * upstream )